Protein and urea resin molding composition and process of making same



, Patented Mar. '30, 1931 UNITED STATES- V 2,075,276 raorem AND UREAaesm momma COMPOSITION MAKING SAME AND PROCESS OF Carleton Montclair, N.1., assignor to Ellis- Foster Company, a corporation 01' New Jersey NoDrawing. Application September 11, 1935,

' Serial No. 40,091

16 Claims. (01. 106-22) This invention relates to molding compositionsand molded products and to the process of making same and particularlyto materials prepared from urea resins with substances of that classknown as proteins which on hydrolysis form amino acids and which includewater-soluble or water-sensitive bodies such as casein, gelatin,

glue, zein, sericin and albumin, and water-insoluble bodies comprisingcollagens, fibroids.

silk, fur, feathers, keratin, dried blood'and leather scrap.

In various copending applications I have de-.

scribed the use of protein materials with ureaformaldehyde condensationproducts to form hot-molding compositions. For example, in Serial No.689,165, filed Jan. 28, 1924, entitled White synthetic resin and processof mamng same," I have disclosed and claimed shaped articles containingthe reaction product of urea and iormaldehyde, and an acid. Casein andgelatin are set forth therein as modifying or tempering agents and otherspecific ingredients of the composition include silk flock and leatherscrap. Further, in Serial No. 694,420, filed Feb. 21, 1924, entitledWhite plastic resin and process of making same, wherein is disclosed andclaimed molded articles comprising heat-set 3o urea-formaldehyderesin"'containing an .acid catalyst, the use ofwool flock, silk flockand ground or comminuted' leather scrap is described.

It is an object of this invention to prepare hotmolding compositionswhich can be molded to form articles having improved translucency,strength, flexibility, and also, in many cases, lower cost than whencellulose is used as the reinforcing agent for the molded article.

Another object is to provide compositions which can be hot-molded toform translucent articles of the nature of threaded bottle caps whichwhen hot (freshly formed) are flexible enough to be sprung off thethreaded projection of the mold rather-than unscrewed. p It is a furtherobject to prepare homogeneous molded articles from urea resin andproteins.

Protein materials and urea-formaldehyde condensation products arenitrogenous. Rather surprisingly it has been found that urea resin 50,evinces a pronounced affinity for the water-insoluble proteins. Theamnity between a waterinsoluble protein such as hair and a urea-formaldehyde condensation product can be shown by mixing the two substancesand hot-pressing,

keratoids and chitinoids and exemplified by wool,

the other hand, when urea-formaldehyde is replaced by aphenol-formaldehyde resin (non-nitrogenous) and hot-pressed, an entirelydifferent result is obtained. The article has little strength and thehair is readily distinguishable since there is no cementing of resin andfiber. For present purposesit is immaterial whether the differencebetween urea-formaldehyde and phenol-formaldehyde in this respect is dueto actual combination with the fiber in the case of urea-formaldehyde orto difierences in adhesion of the two resins to the water-insolubleprotein. The results are entirely different.

Besides being nitrogenous and hydrolyzableto amino acids, proteins arereactive with formaldehyde. They may therefore be reacted with for?maldehyde before incorporation with the urea resin composition or theymay be used in their'. normal form, in which case during drying ormolding they tend to react with any formaldehyde which is released bythe curing of the methylol compounds, thereby reducing blistering of themolded article.

The urea resin employed is preferably that pro.- duced by reaction ofurea and formaldehyde, including formalin and formaldehyde polymers,

paraiorm and so forth, or substances of equivalent behavior. In additionto urea various urea derivatives, thiourea, guanidine. compounds and Ithe like or mixtures of these may be used; Formaldehyde likewise may bereplaced in whole or "in part by other aldehydes including, for example,acetaldehyde.

The method of incorporating urea-formaldehyde with proteins is to mixthe aqueous urea resin syrup, such as obtained .by reaction of a -orotherwise, and a catalyst to facilitate curing (e. g., glyceroldichlorohydrin) and a mold lubricant (zinc or aluminum stearate,petrolatum etc.) as well as pigments and dyes, are added at some stageduring the grinding.

If desired, the protein material may be introducd into the initialmixture of urea and for- .malin, thereby securing the advantage ofcoresinification between formaldehyde, urea and protein.

The following, examples illustrate various ways of carrying out thisinvention. Parts are by weight.

A urea resin syrup was prepared by refluxing together for 1 hour and 30minutes 1120 parts of 37% aqueous formaldehyde (pH 7.0), 0.5 part ofmagnesium carbonate and 552 parts of urea. The pH of the mixture waskept at 7.0 during the first few minutes of boiling by adding-occasionaldrops of sodium hydroxide. This waterwhite solution was used withvarious proteins and will be referred to hereinafter as the resin syrup;Although the above represents the preferred composition and method ofmaking the 1 urea resin, the proportions and .conditions can be .varieddepending upon specific requirements.

Example 1 and had a fair glaze. The material had a soft 4 flow.

Example 2 200parts resin syrup and 28 parts wool yarn (pH=5.-5) were airdried for 48 hours, then at 70 C. for 3 hours. The dried material wasground in a ball mill after which 1 cc. glycerol dichlorhydrin and 0.25g. zincistearate per 100 g. composition were added..

When molded at140 C., 3500 lb. per sq. in.,' for 5 minutes, the fiow wasgood, the color white, the translucency fair, glaze good and strengthexcellent} When a molding was boiled in water for 15 minutes, the glosswas very slightly reduced but it was otherwise unaffected.

Example 3 Leather scrap was washed several times with water,dflutesodium carbonate, and again with water. The pH was then" 6.5. Thescrap (70 parts) was then with 200 parts resin syrup and allowed toair-dry for 48Ihours after which drying .was continued at 70 C. for 3hours.

Grinding to a fine powder was. done in a ball mill and in the finalstage of grinding curing catalyst and mold lubricant were added in thepropor- Example 4 200 parts resin syrup and 100 parts casein were mixed,dried; ground, 'activatedand lubricated 5 as in Example 2. J Thematerial when molded at 140 C., 3500 lb. per sq. in., for 5 minutes wasrather hard flowing and gavemoldings of a light grayish color, opaque,and not very well glazed.

Examp 5;

mm casein were digested with '200 parts of cold-37% formaldehyde and 200parts of water. The washed and filtered product was incorporated with200 parts resin syrup, dried at 70 0., ground,

and activated and lubricated as in Example 2.

'as in Example 11.

The material was molded in a cup die at 140 C. for 5 minutes, and at 160C. for 3 minutes, at 3500 lb. per sq. in. The flow was greatly improvedover that of the composition of Example 4. Wellformed, light gray,'quitetranslucent, strong cups were obtained.

Example 6 200 parts resin syrup and 60 parts glue were treated as inExample 2. When molded at 140 C., 3500 lb. per sq. in., for 5 minutes,the composition was found to be somewhat hard flowing. The cups producedwere rather dark colored and quite translucent.

Example 7 200 parts resin syrup and 70 parts-dried egg albumin weretreated as in Example 2. When molded at C. and at C., 3500 lb. per sq.in. for 5 minutes the composition was soft flowing. Well formed moldingswere produced which had a slightly satiny glaze and.high translucency,it being possible to read through sections 1 mm.

- in thickness it held on a printed page. The moldings were verybrittle, however, and required the addition of fibrous material toimpart strength.

Example 8 Example 9.

200 parts resin syrup and 50parts zein were treated as in Example 2. v

When molded at 140 0., 3500 lb. per sq. in.,

for 5 minutes the powder was found to be soft flowing. The moldedarticle thus produced was I -nicely formed, highly glazed, quitetranslucent, flexible when hot, and of an olive-green color.

. When molded as above for 13 minutes the appearance'was unchanged andthe cup was'lessaffected by prolonged boiling in water.

Example 10 62 parts dark-colored hair were washed with water andisopropyl alcohol, dried. and mixed with 200 parts resin syrup. The mixwas dried at 70 C. and treated as in Example 2.

When-molded at 140 C., 3500 lb. per sq. in., for 5 and 8 minutes, theflow was soft, well-formed,

I black, strong moldings being-obtained.

' Emple 11- Equal parts of molding compositions described in Examples 1.and 2 were thoroughlymixed and molded at 140 C., 3500 lb. per sq. in-.,for 5 minutes. The moldings thus produced were nicely formed and strong.The translucency was about the same as that of the moldings of Example1.

Eisample 12 Equal parts of molding compositions of Examples 2 and 7 werethoroughly'mixed and molded The articles were light colored, strong andtranslucent.

All the above compositions gave molded articles which were mechanicallystrong when cold. When taken hot from the mold all possessed a degree offlexibility. (thermoelasticity), and had sufiicient elasticity so thaton deformation the tendency was to spring back into the original shape.This property is important in enabling articles to be removed from themold with less danger of breakage than with compositions which on comingfrom the mold are more brittle, such as molded articles containingcellulose filler. Also, as noted above, this property enables molding instripping dies to give rapid production of threaded articles. Cellulosefiller can be added to the compositions, the amount of celluloseutilized being insuflicient to counteract the thermoelasticity impartedby the protein material.

Although the above compositions are described in relation to hot-moldingin closed dies, they are also adapted to extrusion molding on ac countof their relatively easy flow.

What I claim is:

l. A urea-aldehyde-resin molding composition comprising urea-aldehyderesin and a protein substance.

2.' A urea-formaldehyde resin composition comprising urea-formaldehyderesin and-a protein substance, said composition being capable onhot-molding of yieldingptrong, translucent articles possessingthermoelasticity.

3. A urea-aldehyde resin composition comprising urea-aldehyde resin anda water-insoluble protein substance, said composition being capable onhot-molding of yielding strong translucent articles possessingthermoelasticity.

4. A urea-aldehyde resin molding composition comprising urea-aldehyderesin and a waterinsoluble protein substance selected from the groupconsisting of collagens, flbroids, keratoids,

and chitinoids.

v5. A urea-aldehyde resin moldingcomposition comprising urea-aldehyderesin, a protein substance and a cellulose tiller.

8. Process of making a molding composition which comprises incorporatinga urea-aldehyde resin syrup with a protein substance and drying themixture.

,7. Process of making a molding compositio which comprises incorporatinga urea-formaldehyde resin syrup with a protein substance and drying themixture.

8. Process of making a molding composition which comprises incorporatinga urea-aldehyde resin syrup with a water insoluble protein substanceselected from the group consisting of collagens, flbroids, keratoids andchitinoids and drying the mixture.

9. A 'molding composition obtainable by the process of claim 6.

10. A molding composition of the type obtainable by the process of claim7.

11. A molding composition ofthe type obtainable by the process of claim8.

12. A urea-aldehyde resin molding composition comprising a glycerolhalo-hydrine and the product obtained by incorporating urea-aldehyderesin syrup with a protein substance and drying the resulting mixture.

13. A molding composition according to claim 12, in which the glycerolhalo-hydrine is glycerol dichlorhydrine and the protein substance iszein.

14. Process of forming urea-aldehyde resin article which comprisessubjecting the mixture obtained by incorporating a urea-aldehyde resinthe mixture subjected to the hot pressing operation contains glyceroldichlorhydrine.-

SARLETON Ems.

syrup with a protein substance and drying thev I

